1000 resultados para Comportamento diferido
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Dissertação elaborada no Laboratório Nacional de Engenharia Civil para obtenção do Grau de Mestre em Engenharia Civil no Ramo de Geotecnia pela Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa no âmbito do protocolo de cooperação entre a FCTUNL e o LNEC
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A adequada previsão do comportamento diferido do betão, designadamente da retracção, é essencial no projecto de uma obra de grandes dimensões, permitindo conceber, dimensionar e adoptar as disposições construtivas para um comportamento estrutural que satisfaça os requisitos de segurança, utilização e durabilidade. O actual momento é marcado por uma transição em termos da regulamentação de estruturas, com a eminente substituição da regulamentação nacional por regulamentação europeia. No caso das estruturas de betão, o Regulamento de Estruturas de Betão Armado e Pré-Esforçado (REBAP), em vigor desde 1983, será substituído pelo Eurocódigo 2. Paralelamente, a Federation International du Betón publicou o Model Code 2010 (MC2010), um documento que certamente terá forte influência na evolução da regulamentação das estruturas de betão. Neste contexto, o presente trabalho tem como objectivo estabelecer uma comparação entre os diferentes modelos de previsão da retracção incluídos nos documentos normativos referidos, identificando as principais diferenças e semelhanças entre eles e quantificando a influência dos diferentes factores considerados na sua formulação, de forma a avaliar o impacto que a introdução destes modelos de previsão irá ter no projecto de estruturas de betão. Com o propósito de aferir a forma como estes modelos reflectem a realidade do fenómeno em estudo, procedeu-se à aplicação destes modelos de previsão ao betão de duas obras cujo comportamento estrutural é observado pelo LNEC, concretamente a ponte Miguel Torga, sobre o rio Douro, na Régua, e a ponte sobre o rio Angueira, no distrito de Bragança. Em ambas as obras tinha sido efectuada a caracterização in situ da retracção, tendo-se comparado os valores experimentais assim obtidos com os valores provenientes da aplicação dos modelos de previsão considerados neste trabalho. Finalmente são apresentadas algumas conclusões obtidas com o trabalho desenvolvido nesta dissertação, bem como algumas sugestões para desenvolvimentos futuros.
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Tese de Doutoramento - Civil Engineering
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The objective of this study was to evaluate the productive performance, metabolic and feeding behavior of sheep after ninety days deferred pasture at different heights. The experiment was conducted at Capim Branco experimental farm of the Universidade Federal de Uberlândia. During the period of 90 days, from June to September 2013, forty-eight crossbred lambs Santa Inês x Dorper, divided into groups of four animals, occupied twelve pickets deferred pasture with four initial heights (15 cm, 25 cm, 35 cm and 45 cm). During this period we evaluated the structural characteristics of pasture. For confinement, from September to December 2013, 32 of these animals were used (16 males and 16 females), divided into four bays, separated as pasture were using. The consumption was assessed daily, while biometric measurements were made every 21 days. In relation to gender, there were differences in average daily gain weight. Reviews of feeding behavior occurred at the beginning, middle and end of the experiment for 24 hours. The rumination and leisure activities do not present statistical differences, both initial height of pasture and by period. The time spent on intake was higher during the daytime both treatments starting height as the experimental periods, however, rumination activity was more intense at night. Blood glucose was achieved in five periods of the day, while other metabolites have been obtained with a collection made fortnightly. The different initial heights not promoted effects on blood glucose. The harvesting times were not affected. However, there was a reduction of basal blood glucose of animals throughout the experimental period. There was a significant interaction between the initial pasture heights and periods of evaluation of basal glucose. Cholesterol and triglyceride levels were below recommended levels, however the final phase of confinement cholesterol level increased significantly. The values of VLDL and GGT were above the reference range. FA and AST showed average values within the recommended values. Total protein was influenced by different initial heights of pasture. The creatinine and albumin had values below the recommended range. Moreover, the albumin decreased during the confinement time. Uric acid showed close to the recommended maximum. There was stabilization of compensatory growth, with modification of consumption and weight gain at 45 days of experiment.
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Antimicrobials, among other veterinary drugs, are used worldwide in industry and agriculture to protect animal health and prevent economic loss. In recent years, they have been detected in various environmental compartments, including soil, surface and groundwater and have become a topic of research interest. Emphasizing this class of compounds, this review presents the different pathways which veterinary drugs enter in the environment, in particular contaminate soils. Also are presented regulatory aspects and guidelines, adsorption/desorption and degradation of these compounds in soils and the consequences of its dispersal in the environment.
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The efficiency of swine production performance depends on the herd administration, such as good nutrition, sanitary control, facilities and appropriate environmental conditions. The concept of this production model is directly related with the reduction of selective losses and the process control. Each production segment is controlled to reach the optimization in the system totality, it is necessary to apply animals handling concepts, environmental control implementation, diseases control, nutrition control, information concerning in guaranteeing the animal welfare and individual identification. The present work presents as objective the development of the mathematical model to evaluate interactions among the internal atmosphere of the installation and the thermal animals preference, in the expectation of detecting a relationship among the frequency access to the drinking fountain and the atmosphere conditions - temperature, black globe temperature and relative humidity, using as tool the electronic identification. The results obtained by the mathematical model, allowed to conclude accurately the evaluation of the swine thermal preference correlating with the climatic variables in the pregnancy stage.
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Behavioral adaptiveness to different situations as well as behavioral individuality result from the interrelations between environmental sitmuli and the responses of an organism.These kind of interrelationships also shape the neural circuits as well as characterize the plasticity and the neural individuality of the organism. Studies on neural plasticity may analyze changes in neural circuitry after environmental manipulations or changes in behavior after lesions in the nervous system. Issues on neural plasticity and recovery of function refer both to physiology and behavior as well as to the subjacent mechanisms related to morphology, biochemistry and genetics. They may be approached at the systemic, behavioral, cellular and molecular levels. This work intends to characterize these kinds of studies pointing to their relations with the analyis of behavior and learning.The analysis of how the environmental-organismic interrelationships affect the neural substrates of behavior is pointed as a very stimulating area for investigation.
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This research intended to investigate the use of diazepam in conjunction with behavioral strategies to manage uncooperative behavior of child dental patients. The 6 participants received dental treatment during 9 sessions. Using a double-blind design, children received placebo or diazepam and at the same time were submitted to behavior management produces (distraction, explanation, reinforcement and set rule and limits). All sessions were recorded in video-tapes biped in 15 seconds intervals, in which observers recorded child's (crying, body and/or head movements, escape and avoidance) and dentist's behavior. The results indicated that diazepam, considering the used dose, was only effective with one subject. The other participants didn't permit the treatment and showed an increase in their resistance. The behavioral preparation strategies for dental treatment should have been more precisely planned in order to help the child to face the real dental treatment conditions mainly in the first sessions avoiding to reinforce inappropriate behaviors.
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The present investigation evaluated the effects of diazepam used to manage uncooperative behavior of child dental patients. Six participants received placebo or diazepam (0,3 mg/kg weight) before formal dental treatment at total 54 sessions that were all recorded in videotapes. The analysis of recorded child (crying, body and/or head movements, escape and avoidance) and dentist's behavior management procedures (distraction, explanation, positive reinforcement) indicates no differences by using a double-blind Wilcoxon design (p>0.05). It is suggested the necessity of methodological refinement in studies that combine psychological and pharmacological handling strategies.
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BACKGROUND: Changes in heart rate during rest-exercise transition can be characterized by the application of mathematical calculations, such as deltas 0-10 and 0-30 seconds to infer on the parasympathetic nervous system and linear regression and delta applied to data range from 60 to 240 seconds to infer on the sympathetic nervous system. The objective of this study was to test the hypothesis that young and middle-aged subjects have different heart rate responses in exercise of moderate and intense intensity, with different mathematical calculations. METHODS: Seven middle-aged men and ten young men apparently healthy were subject to constant load tests (intense and moderate) in cycle ergometer. The heart rate data were submitted to analysis of deltas (0-10, 0-30 and 60-240 seconds) and simple linear regression (60-240 seconds). The parameters obtained from simple linear regression analysis were: intercept and slope angle. We used the Shapiro-Wilk test to check the distribution of data and the t test for unpaired comparisons between groups. The level of statistical significance was 5%. RESULTS: The value of the intercept and delta 0-10 seconds was lower in middle age in two loads tested and the inclination angle was lower in moderate exercise in middle age. CONCLUSION: The young subjects present greater magnitude of vagal withdrawal in the initial stage of the HR response during constant load exercise and higher speed of adjustment of sympathetic response in moderate exercise.
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OBJECTIVE: To characterize the behavior of premature newborns in the first year of chronological age. METHODS: This is a cross-sectional descriptive study, bound to a longitudinal study titled: Comparison of visual behavior on the first quarter of year of life of premature nursling born at two maternities of Recife/PE. The sample was composed by 52 premature newborns selected from June, 2007 to June, 2008 from the Maternity of the Federal University of Pernambuco (UFPE). Biological, socioeconomic and demographic data was collected through medical records and interviews with progeny. Newborns were evaluated by the Assessment Guide of Visual Ability in Infants. RESULTS: Most of the newborns were male at a gestational period between 33 weeks and 36 weeks and 6 days, showed a good visual behavior development for the age researched, and most of the families showed good socioeconomical and demographic profile. Besides, it was possible to detect ocular signs in 19% of sample, that were referred to an Ophthalmology Service. CONCLUSION: This study results point out the method like an important key in the early detection and visual screening for premature nursling since the first month of life and it led us to believe that clinical view for occupational therapy intervention must be focused not only on biological risks but also at the influence environment in newborn performance.
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Universidade Estadual de Campinas . Faculdade de Educação Física
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Universidade Estadual de Campinas . Faculdade de Educação Física
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Universidade Estadual de Campinas . Faculdade de Educação Física
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Universidade Estadual de Campinas . Faculdade de Educação Física